Add tests for multiple stubs with Arguments::any()
Fix stubbing with a AnyInstance argument after having stubbed with a specific instance argument
Fix stubbing without arguments after having stubbed with an AnyInstance argument
Allow for many more combinations of overloading stubs with various wildcards

- Allow multiple stubbing with anything arguments in different positions
- Allow adding a stub with a specific instance argument after having added a stub with an any instance argument
- Ensure that stubs with more specific arguments get priority over more generic ones
Merge pull request #210 from pivotal-brian-croom/multiple-stubs-with-anything

Multiple stubs with anything